|
| 1 | +#!/usr/bin/env python |
| 2 | + |
| 3 | +"""Find the best reviewer(s) for a given changeset. |
| 4 | +
|
| 5 | +This works under both git and mercurial. |
| 6 | +
|
| 7 | +1) Runs 'hg diff <argv>' (so by default, diffs all currently edited files). |
| 8 | + or 'git diff <argv>'. |
| 9 | +2) Analyzes the diff to find out exact lines that have changed. |
| 10 | +3) Runs 'hg/git blame' to figure out who last modified those lines. |
| 11 | +4) For each file, prints the usernames who last-modified any of the |
| 12 | + diffed lines in the file, along with how many of the lines they |
| 13 | + modified. |
| 14 | +
|
| 15 | +The idea is that if one user has modified all the lines you are |
| 16 | +editing, they are a good candidate to review your change. |
| 17 | +""" |
| 18 | + |
| 19 | +import os |
| 20 | +import re |
| 21 | +import sys |
| 22 | +import subprocess |
| 23 | + |
| 24 | + |
| 25 | +# The line we care about in the diff output is |
| 26 | +# @@ -<startline>,<numlines> ... |
| 27 | +# or @@ -<startline> ... # in which <numlines> is taken to be 1 |
| 28 | +# (Everything else is header or diff content, which we ignore.) |
| 29 | +_DIFFLINE_RE = re.compile('^@@ -(\d+)(?:,(\d+))? ') |
| 30 | + |
| 31 | +_NEWFILE_RE = re.compile('^--- (.*)') |
| 32 | + |
| 33 | + |
| 34 | +class Mercurial(object): |
| 35 | + def __init__(self, ui, repo): |
| 36 | + self.ui = ui |
| 37 | + self.repo = repo |
| 38 | + |
| 39 | + def write(self, msg): |
| 40 | + self.ui.write(msg) |
| 41 | + |
| 42 | + def find_wholefile_lines(self, files, revision='.'): |
| 43 | + """Return a map from abspath -> set-of-all-linumbers in the file.""" |
| 44 | + ctx = self.repo[revision] # state of repository base revision |
| 45 | + m = ctx.match(files, None, None, 'relpath') |
| 46 | + all_files = ctx.walk(m) |
| 47 | + |
| 48 | + all_lines = {} |
| 49 | + for abspath in all_files: |
| 50 | + before_text = ctx.filectx(abspath).data() |
| 51 | + num_lines = before_text.count('\n') |
| 52 | + all_lines[abspath] = set(range(1, num_lines + 1)) |
| 53 | + |
| 54 | + return all_lines |
| 55 | + |
| 56 | + def find_modified_lines(self, files, revision='.'): |
| 57 | + """Return a map from abspath -> set-of-linenumbers changed.""" |
| 58 | + import mercurial.mdiff |
| 59 | + |
| 60 | + ctx = self.repo[revision] # state of repository base revision |
| 61 | + edit_ctx = self.repo[None] # current working state ('.' + local edits) |
| 62 | + |
| 63 | + # Find the files that have modifications. |
| 64 | + m = ctx.match(files, None, None, 'relpath') |
| 65 | + # Only count files that have been edited from tip. |
| 66 | + modified = self.repo.status(ctx, None, match=m)[0] |
| 67 | + |
| 68 | + modified_lines = {} |
| 69 | + diffopts = mercurial.mdiff.diffopts(context=0, nodates=True) |
| 70 | + for abspath in modified: |
| 71 | + before_text = ctx.filectx(abspath).data() |
| 72 | + after_text = edit_ctx.filectx(abspath).data() |
| 73 | + diff_text = mercurial.mdiff.unidiff( |
| 74 | + before_text, None, after_text, None, |
| 75 | + abspath, abspath, opts=diffopts) |
| 76 | + # Look at the '@@ -<startline>,<numlines> ...' diffline to |
| 77 | + # find what lines in the input file were changed. |
| 78 | + modified_lines.setdefault(abspath, set()) |
| 79 | + for line in diff_text.splitlines(): |
| 80 | + m = _DIFFLINE_RE.match(line) |
| 81 | + if m: |
| 82 | + startline, n = int(m.group(1)), int(m.group(2) or '1') |
| 83 | + modified_lines[abspath].update(range(startline, |
| 84 | + startline + n)) |
| 85 | + |
| 86 | + return modified_lines |
| 87 | + |
| 88 | + def get_annotation_info(self, abspaths, revision='.'): |
| 89 | + """Return a map abspath -> list-of-author-names. |
| 90 | +
|
| 91 | + retval[filename][i] says who wrote the i-th line of the file. |
| 92 | + Line numbers start at 1, so retval[filename][0] is always None. |
| 93 | + """ |
| 94 | + retval = {} |
| 95 | + user_to_shortuser = {} |
| 96 | + |
| 97 | + ctx = self.repo[revision] # state of repository base revision |
| 98 | + for abspath in abspaths: |
| 99 | + retval[abspath] = [None] |
| 100 | + anno_lines = ctx[abspath].annotate(follow=True) |
| 101 | + for anno_line in anno_lines: |
| 102 | + modifier = anno_line[0].user() |
| 103 | + if modifier not in user_to_shortuser: |
| 104 | + user_to_shortuser[modifier] = self.ui.shortuser(modifier) |
| 105 | + retval[abspath].append(user_to_shortuser[modifier]) |
| 106 | + |
| 107 | + return retval |
| 108 | + |
| 109 | + |
| 110 | +class Git(object): |
| 111 | + def write(self, msg): |
| 112 | + sys.stdout.write(msg) |
| 113 | + |
| 114 | + def find_wholefile_lines(self, files, revision='HEAD'): |
| 115 | + """Return a map from abspath -> set-of-all-linumbers in the file.""" |
| 116 | + all_lines = {} |
| 117 | + for f in files: |
| 118 | + before_text = subprocess.check_output(['git', 'show', |
| 119 | + '%s:%s' % (revision, f)]) |
| 120 | + num_lines = before_text.count('\n') |
| 121 | + all_lines[os.path.abspath(f)] = set(range(1, num_lines + 1)) |
| 122 | + return all_lines |
| 123 | + |
| 124 | + def find_modified_lines(self, files, revision='HEAD'): |
| 125 | + """Return a map from abspath -> set-of-linenumbers changed.""" |
| 126 | + modified_lines = {} |
| 127 | + |
| 128 | + # Only count Deleted and Modified files. |
| 129 | + diff_output = subprocess.check_output(['git', 'diff', '-U0', |
| 130 | + '--diff-filter=DM', |
| 131 | + '--no-ext-diff', '--no-prefix', |
| 132 | + revision, '--'] + files) |
| 133 | + abspath = None |
| 134 | + for line in diff_output.splitlines(): |
| 135 | + m = _NEWFILE_RE.match(line) |
| 136 | + if m: |
| 137 | + abspath = os.path.abspath(m.group(1)) |
| 138 | + modified_lines[abspath] = set() |
| 139 | + else: |
| 140 | + m = _DIFFLINE_RE.match(line) |
| 141 | + if m: |
| 142 | + assert abspath, line # filename comes before diff info |
| 143 | + startline, n = int(m.group(1)), int(m.group(2) or '1') |
| 144 | + modified_lines[abspath].update(range(startline, |
| 145 | + startline + n)) |
| 146 | + |
| 147 | + return modified_lines |
| 148 | + |
| 149 | + def get_annotation_info(self, abspaths, revision='HEAD'): |
| 150 | + """Return a map abspath -> list-of-author-nqames. |
| 151 | +
|
| 152 | + retval[filename][i] says who wrote the i-th line of the file. |
| 153 | + Line numbers start at 1, so retval[filename][0] is always None. |
| 154 | + """ |
| 155 | + retval = {} |
| 156 | + author_re = re.compile(r'author-mail <([^>]*)>') |
| 157 | + |
| 158 | + for abspath in abspaths: |
| 159 | + retval[abspath] = [None] |
| 160 | + # TODO(csilvers): also specify -C? |
| 161 | + blame_output = subprocess.check_output(['git', 'blame', '-M', |
| 162 | + '--line-porcelain', |
| 163 | + revision, '--', abspath]) |
| 164 | + for line in blame_output.splitlines(): |
| 165 | + m = author_re.match(line) |
| 166 | + if m: |
| 167 | + author = m.group(1) |
| 168 | + # Just to make the common-case output prettier. |
| 169 | + if author.endswith('@khanacademy.org'): |
| 170 | + author = author[:-len('@khanacademy.org')] |
| 171 | + retval[abspath].append(author) |
| 172 | + |
| 173 | + return retval |
| 174 | + |
| 175 | + |
| 176 | +def findreviewers(vcs, files, revision=None, num_reviewers=3, |
| 177 | + whole_file=False, output_per_file=False, ignore=[]): |
| 178 | + """Find the best reviewer(s) for a given changeset. |
| 179 | +
|
| 180 | + Examines the current changes in this file, and runs 'hg blame' or |
| 181 | + 'git blame' (depending on 'vcs') to find who last edited those |
| 182 | + same lines. Collates and returns this information, including how |
| 183 | + many lines each person is responsible for. |
| 184 | +
|
| 185 | + Arguments: |
| 186 | + vcs: either a Mercurial or a Git instance, from this file. |
| 187 | + files: a list of filenames to find reviewer information for |
| 188 | + revision: what revision to diff against when looking for |
| 189 | + reviewers (typically '.' for mercurial or 'HEAD' for git). |
| 190 | + num_reviewers: the number of reviewers to suggest for each file. |
| 191 | + 3 is a reasonable value. |
| 192 | + whole_file: if True, return reviewer information for the input |
| 193 | + files as a whole, not just for the diff vs 'revision'. This |
| 194 | + is useful when you want to know who is 'most responsible' for |
| 195 | + a file. |
| 196 | + output_per_file: if True, instead of printing the best reviewers |
| 197 | + for the set of input files as a whole, prints a separate list |
| 198 | + of best reviewers for each file in the input. |
| 199 | + ignore: a set/list of revisions to ignore when finding blame info. |
| 200 | + TODO(csilvers): implement this. |
| 201 | + """ |
| 202 | + # revision has to be a kwarg because of how findreviewers() is |
| 203 | + # called, but it's actually required. |
| 204 | + assert revision, 'revision argument cannot be None!' |
| 205 | + |
| 206 | + if whole_file: |
| 207 | + modified_lines = vcs.find_wholefile_lines(files, revision) |
| 208 | + else: |
| 209 | + modified_lines = vcs.find_modified_lines(files, revision) |
| 210 | + |
| 211 | + annotation_info = vcs.get_annotation_info(modified_lines.keys(), revision) |
| 212 | + |
| 213 | + if output_per_file: |
| 214 | + # filename -> {author: num_lines, ...} |
| 215 | + num_lines_per_author = {abspath: {} for abspath in modified_lines} |
| 216 | + else: |
| 217 | + # None -> {author: num_lines, ...} |
| 218 | + num_lines_per_author = {None: {}} |
| 219 | + |
| 220 | + for abspath in modified_lines: |
| 221 | + for linenum in modified_lines[abspath]: |
| 222 | + author = annotation_info[abspath][linenum] |
| 223 | + if output_per_file: |
| 224 | + num_lines_per_author[abspath].setdefault(author, 0) |
| 225 | + num_lines_per_author[abspath][author] += 1 |
| 226 | + else: |
| 227 | + # Just store global info |
| 228 | + num_lines_per_author[None].setdefault(author, 0) |
| 229 | + num_lines_per_author[None][author] += 1 |
| 230 | + |
| 231 | + # Print the information out. |
| 232 | + for abspath in sorted(num_lines_per_author.iterkeys()): |
| 233 | + if abspath: |
| 234 | + vcs.write('\n--- %s\n' % abspath) |
| 235 | + |
| 236 | + reviewers = num_lines_per_author[abspath].items() |
| 237 | + reviewers.sort(key=lambda (_, num_lines): num_lines, reverse=True) |
| 238 | + total_lines = sum(num_lines_per_author[abspath].itervalues()) |
| 239 | + |
| 240 | + for (reviewer, reviewer_num_lines) in reviewers[:num_reviewers]: |
| 241 | + vcs.write('%s: %s lines (%.1f%%)\n' |
| 242 | + % (reviewer, reviewer_num_lines, |
| 243 | + reviewer_num_lines * 100.0 / total_lines)) |
| 244 | + |
| 245 | + |
| 246 | +# How hg uses this script: via the cmdtable hook. |
| 247 | +cmdtable = { |
| 248 | + 'findreviewers': |
| 249 | + (lambda ui, repo, *files, **opts: ( |
| 250 | + findreviewers(Mercurial(ui, repo), files, **opts)), |
| 251 | + [('f', 'output-per-file', None, 'Print results per input file'), |
| 252 | + ('n', 'num-reviewers', 3, 'How many reviewers to show'), |
| 253 | + ('w', 'whole-file', None, 'Calculate reviewers based on entire file'), |
| 254 | + ('i', 'ignore', [], 'TODO: Revisions to ignore when annotating'), |
| 255 | + ('r', 'revision', '.', 'Revision to use as base'), |
| 256 | + ], |
| 257 | + '[-f] [-n #] [-w] [-i <commit_id> ...] [FILE...]') |
| 258 | + } |
| 259 | + |
| 260 | + |
| 261 | +# How git uses this script: via __main__ |
| 262 | +if __name__ == '__main__': |
| 263 | + import argparse |
| 264 | + parser = argparse.ArgumentParser(description=__doc__) |
| 265 | + |
| 266 | + parser.add_argument('files', nargs='*') |
| 267 | + for (shortname, longname, default, help) in cmdtable['findreviewers'][1]: |
| 268 | + if default is None: |
| 269 | + parser.add_argument('--%s' % longname, '-%s' % shortname, |
| 270 | + help=help, default=default, |
| 271 | + action='store_true') |
| 272 | + else: |
| 273 | + parser.add_argument('--%s' % longname, '-%s' % shortname, |
| 274 | + help=help, default=default, |
| 275 | + type=type(default)) |
| 276 | + # The one place we differ from the mercurial defaults. |
| 277 | + parser.set_defaults(revision='HEAD') |
| 278 | + |
| 279 | + args = parser.parse_args() |
| 280 | + |
| 281 | + findreviewers(Git(), **args.__dict__) |
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